Drawing ruler lines


I need to draw ruler lines (parallel to axes) intersecting
the mouse pointer position. That is:
         y> >



          > >
          > >
          > >
          > >
          > >

I'm not sure where is the best place to do such a thing:
if at renderer or at artist level. The rulers
must follow the mouse and everytime they are
moved the contents "below" them must be restored.
I don't know how to do it (to save the underlying
contents before rendering the ruler). Another matter
is tranformation between data and screen coordinates,
how could I do it? I played a little
with events, line artist and with the renderer api but
I would welcome any clue from you.

Thank you in advance.

1GB gratis, Antivirus y Antispam
Correo Yahoo!, el mejor correo web del mundo